WINEMAKERS and vignerons in Western Australia can use an online tool to identify the danger periods for smoke taint from burning off or bushfires during the coming fruit production season.
The Smoke Taint Risk calculator (STAR) was developed to reduce the incidence and severity of smoke exposure on grapes and wine.
Researchers at the Department of Agriculture and Food and the University of Western Australia developed the tool with co-funding from the Australian Grape and Wine Authority.
Department senior research officer Glynn Ward said STAR was useful for assessing the smoke taint risk for grape varieties Merlot, Cabernet Sauvignon, Chardonnay and Sauvignon Blanc.
“Smoke exposure of grapes during sensitive growth stages can result in wine with unwanted smoke-related aromas and flavours, such as smoked meat, disinfectant and ashtrays,” Mr Ward said.
“In order to protect Western Australia’s premium wine sales in both domestic and international markets, it is vital the issue of smoke taint is addressed as best possible.
“Research has shown the risk of smoke taint and development varies depending on the vine growth stage.
“STAR uses a growth model based on temperature to predict the seasonal grapevine growth stages for different wine grape varieties.
“Users can input data at any time of the season to predict and graph the smoke taint risk in many Australian grape growing regions.
“The tool can also be applied by land and forest managers in deciding on the timing of fuel reduction burns to avoid periods when grapes are most susceptible to smoke.”
STAR includes function such as vineyard location mapping, seasonal growth stages, smoke risk factors based on the chemical and sensory properties of wine, and in-field smoke detecting equipment where relevant.
Mr Ward said since it was launched late last year, STAR had been utilised by wine grape producers and land managers to help them decide on smoke taint reduction strategies in vineyards and wineries.
“To best understand the timing, density and duration of smoke exposure, and the likelihood of taint in wine, smoke detection equipment can be employed in the vineyard,” he said.
“Strategies to reduce the risk of smoke taint include communicating with land managers, registering sensitive sites by emailing sensitivesites@agric.wa.gov.au, and advising regional wine producing associations of end-of-harvest dates.
“When a smoke event has occurred, winemakers are encouraged to sample and test grapes and wine, and implement vineyard and wine production techniques to reduce smoke taint in wine.
“For example, grapes can be sampled and tested for key smoke compounds prior to harvest to indicate if there is a risk to the final wine.
“Techniques such as hand harvesting of fruit, whole bunch pressing and minimising fermentation time on skins can also be used to reduce smoke characters in wine.”
The Smoke Taint Risk Calculator is published on the department website agric.wa.gov.au More information on the department’s long-running research on the effect of smoke on grapes and wine is also available on the department website, search for ‘smoke taint’.
